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91.
PURPOSE: To report a new eyedrop dispensing container that allows administration of eyedrops while the head of the patient is in the usual upright position. METHODS: An eyedrop dispensing container with a dip tube extending to the bottom, an automatic venting mechanism, and an angulated dispensing tube was developed. RESULTS: The problem of unwanted efflux of fluid was solved by incorporating the automatic venting mechanism. The final design includes an adjustable, angulated dispensing tube and "single structure" construction incorporating the cap. A removable cheek rest is also provided. The design allows eyedrops to be instilled while the patient's head is in the upright position and even when spectacles are being worn. A prototype 15-ml bottle delivered an eyedrop volume of 19.7+/-1.2 microl (mean +/- SD) (n = 75). CONCLUSION: This new eyedrop bottle should allow precise self-administration of eyedrops by a patient in front of a mirror, without a need to change head position.  相似文献   
92.

Purpose

The effect of wide excision of the neurovascular bundles on disease-free survival was determined in men with clinically localized prostate cancer and pathological evidence of extensive capsular perforation in the region of the neurovascular bundle.

Materials and Methods

We previously analyzed 107 men with clinically localized prostate cancer and pathological evidence of extensive capsular perforation in the region of the neurovascular bundles. Wide excision of the neurovascular bundle on the sides of palpable induration resulted in negative surgical margins in 58 percent of patients compared to only 45 percent in whom the neurovascular bundles were left intact (p = 0.03). At a mean followup of 20 months, median interval to disease recurrence as defined by a measurable PSA level was 33 months in patients whose neurovascular bundle(s) were widely excised versus 22 months in those whose neurovascular bundle(s) were left intact (p = 0.03). However, by 43 months 75 percent of the patients in both groups had a detectable prostate specific antigen and the Kaplan-Meier curves had converged, suggesting that wide excision of the neurovascular bundle(s) did not confer a sustained survival advantage.

Results

With an additional followup of 28 months, the probability of having an undetectable prostate specific antigen level at 5 years was 47 percent in patients with negative versus 6 percent with positive surgical margins (p less than 0.001).

Conclusions

Our extended followup suggests that some patients with extensive capsular perforation can be rendered free of disease with wide excision of the neurovascular bundle(s).  相似文献   
93.
Bone marrow (BM) environment is thought to support the growth of myeloma cells and thus to play an important role in the pathogenesis of multiple myeloma (MM). Because interleukin-6 (IL-6) is an essential growth factor in MM, we have examined the effects of two myeloma cell lines (U266 and ARH-77) on the IL-6 production by BM stromal cells in a co-culture system. These cell lines strongly stimulate the IL-6 production and IL-6 triggering was partially dependent on physical contact between lines and stroma. The percentages of cell adhesion to stromal layers were 39% and 25% respectively for ARH77 and U266 cell lines. Inhibition studies with blocking monoclonal antibodies showed the importance of CD49d/CD106 and CD11a/CD54 interactions in the stimulation of IL-6 production by stromal cells. However, cell-to-cell contact was not an absolute requirement for IL-6 production. Cytokines, of which TNF-alpha and IL-1beta produced by MM or accessory cells, were also able to stimulate IL-6 production by fibroblasts and show additive effects. In adhesion assays, TNF-alpha and IL-1beta were able to increase the adhesion of MM cells to stromal cells. CD54 was upregulated by IL-1beta, TNF-alpha or a contact with MM cells while CD106 expression was not, suggesting only a functional change of this molecule. However, the role of monoclonal antibodies, directed against these factors, confirmed the role of TNF-alpha in the IL-6 production by stromal cells, while any IL-1beta intervention was not shown in our co-culture system. IL-6 favoured and maintained adhesion of MM cells to stromal cells spontaneously since its reintroduction in the favoured co-culture system restored their decreased adhesion observed on a glutaraldehyde fixed stromal layer. Overall our data suggest a functional overlap between cytokines and adhesion molecules for the paracrine IL-6 production.  相似文献   
94.
Hypertrophic cardiomyopathy (HCM) is an important cause of sudden death in apparently healthy young individuals. In less than half of kindreds with HCM, the disease is linked to the beta-myosin heavy-chain gene locus (MYH7). We have recently described two missense MYH7 gene mutations [Arg-403 to Gln (R403Q) and Leu-908 to Val (L908V)] and found that the mutant message is present in skeletal muscle soleus) and that the mutant beta-myosin obtained from soleus muscle has abnormal in vitro motility activity. Having identified a second kindred with the R403Q mutation, and 3 other kindreds with two additional mutations (G741R and G256E), we performed histochemical analysis of soleus muscle biopsies from 25 HCM patients with one of these four mutations. Light microscopic examination of the NADH-stained biopsies revealed the presence of central core disease (CCD) of skeletal muscle, a rare autosomal dominant nonprogressive myopathy characterized by a predominance of type I "slow" fibers and an absence of mitochondria in the center of many type I fibers. CCD was present in 10 of 13 patients with the L908V mutation, 5 of 8 patients with the R403Q mutation, 1 of 3 patients with the G741R mutation, and 1 patient with the G256E mutation. Mild-to-moderate myopathic changes with muscle fiber hypertrophy were present in 16 patients. Notably, CCD was present in 2 adults and 3 children with the L908V mutation who did not have cardiac hypertrophy. In contrast, soleus muscle samples from 5 patients from 4 kindreds in which HCM was not linked to the MYH7 locus showed no myopathy or CCD. Soleus muscle biopsies from 5 control subjects also showed normal histology. This work demonstrates that (i) MYH7-associated HCM is often a disease of striated muscle but with predominant cardiac involvement and (ii) a subset of HCM patients with MYH7 gene missense mutations have CCD.  相似文献   
95.
96.
The Finapres is a noninvasive monitor that continuously displays the arterial waveform, pulse rate, and systolic, mean, and diastolic blood pressure. We determined its bias (mean prediction error) and precision (mean absolute error), relative to directly measured radial arterial blood pressure, in 16 otherwise healthy patients undergoing spinal fusion surgery under hypotensive anesthetic techniques. Data were recorded during three contiguous epochs: 20 min of normotension; 30 min following the initiation of hypotension; 20 min of hypotension. The Finapres demonstrated a systolic, mean, and diastolic bias (+/- standard deviation) of 3.6 +/- 12.3, 5.2 +/- 10.8, and 8.3 +/- 9.4 mmHg, respectively. There were no significant differences in systolic bias among the epochs, whereas mean and diastolic bias were both greater during the hypotensive epoch, compared to the normotensive epoch. In 2 of the 16 patients, systolic and mean arterial pressure bias exceeded 20 mmHg. Finapres precisions of systolic, mean, and diastolic blood pressures were 9.8 +/- 9.0, 8.7 +/- 7.6, and 10.4 +/- 8.2 mmHg, respectively. Precisions among the epochs were not significantly different. When Finapres pressures were "corrected" by subtracting the baseline difference between Finapres and oscillometrically determined mean pressure, bias decreased significantly. The correction process did not improve precision. The Finapres closely tracked changes in blood pressure, even in the presence of a large bias. In most patients, the Finapres is a useful continuous noninvasive blood pressure monitor. Periodic calibration of the Finapres by the difference between Finapres and oscillometrically determined mean arterial pressure is recommended.  相似文献   
97.
Gene therapy in humans is now being undertaken in an investigational setting. Such therapy involves the administration of biological products to human patients. A document entitled, "Points to Consider in Human Somatic Cell Therapy and Gene Therapy" has been prepared by the Center for Biologics Evaluation and Research (CBER) of the Food and Drug Administration (FDA) and is published elsewhere in this issue. This paper provides explanatory material about the CBER regulatory process and the scientific and regulatory basis for the requests for data in that document.  相似文献   
98.
Dense cystic craniopharyngiomas   总被引:1,自引:0,他引:1  
Characteristic computed tomographic (CT) findings of craniopharyngioma include calcification, contrast enhancement, and cyst formation. Sharp margins associated with a hypodense centrum usually characterize the CT appearance of a cystic tumor. The appearance of "dense" cysts in craniopharyngiomas has not been emphasized. Four cases of craniopharyngiomas with isodense to hyperdense cysts are reported. Comparative biochemical and in vitro CT analysis of cyst aspirates taken from these lesions demonstrate that high intracystic protein concentration accounts for the greater part of the hyperdensity. Various mechanisms for intracystic protein accumulation are discussed. Lesion characteristics, and not necessarily attenuation coefficients, are stressed in differentiating "dense" cystic from solid craniopharyngiomas.  相似文献   
99.
The QT interval was measured in 12 normal and 7 aborted sudden infant death syndrome (SIDS) infants in rapid eye movement (REM) and quiet sleep at monthly intervals through the age of 4 months. An accuracy of better than 2 msec was assured by high resolution of the digitized signal and calibration of each QT measurement with an accurately generated time code. In contrast to current speculations, the QT index was significantly smaller in the infants with aborted SIDS than in the normal infants in both REM and quiet sleep (P less than 0.05). In addition, as in normal infants, the QTc was smaller in REM than in quiet sleep (P less than 0.01). Although these results offer no support for the hypothesis that SIDS results from prolongation of the QT interval, they suggest that aborted SIDS infants have a functional abnormality in the autonomic nervous system.  相似文献   
100.
Incubation of newborn mouse skin in media containing 0.01 M dithiothreitol at 4 degrees C for 2 hr reduces dermal-epidermal cohesion, and the 2 layers may be separated readily. Unlike other methods of separation, this technique does not require heating, nonphysiologic pH or ionic strength, or addition of proteolytic enzymes. The split occurs beneath the basal lamina. The separated epidermal sheet retains the periodic acid Schiff-positive "basement membrane," and the basal cells can incorporate 3H-thymidine.  相似文献   
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